Electronic particle counting for evaluating the quality of air in operating theatres: a potential basis for standards?

Area of Science:

• Environmental Microbiology
• Hospital Engineering
• Air Quality Monitoring

Background:

• Operating theatres require stringent air quality control to prevent surgical site infections.
• Traditional methods for assessing airborne bacteria-carrying particles (BCP) can be time-consuming.
• Electronic particle counters offer a potentially faster method for monitoring air quality.

Purpose of the Study:

• To compare electronic airborne particle counting with slit sampling for BCP assessment.
• To evaluate the effectiveness of electronic particle counting in ultra-clean and turbulently ventilated operating theatres.
• To determine if electronic particle counting can serve as a standard for assessing clean air systems.

Main Methods:

• Airborne particles were counted electronically in eight size ranges (0.5- >20 microns).
• Bacteria-carrying particles (BCP) were assessed using slit sampling.
• Comparisons were made in both ultra-clean and turbulently ventilated operating theatres.

Main Results:

• In ultra-clean theatres, particle counts in the 5-7 micron range correlated with BCP.
• Peaks in particle counts (<3 microns and >15 microns) corresponded with theatre activity.
• Similar relationships were observed in turbulently ventilated theatres, but electronic counting cannot yet replace BCP counts.

Conclusions:

• Electronic particle counting (0-20 microns) can evaluate clean air operating theatre performance.
• This method assesses filter/seal integrity and particle entrainment.
• The described techniques may form a basis for air quality standards in operating theatres.